Motor-compressor unit lubrication



8, 1947. G, MUFFLY 25423,?19

IOTOR-COIIPRBSSOR UNI'I' LUBRiGA'l'ION Filed Jan. 5, 1940 2 Sheets-Sheet1 IN VEN TOR by 67191 Muff/y. M .y'g; sya' Patented July 8, 19 41 UNITEDSTATE s PATENT OFFICE the provision of a motor-compressor unit in whichthe refrigerant introduced into the unit is caused to flow around theperiphery of the motor stator.

before being liberated in the interior of the unit;

the provision 'of a construction as above described in which therefrigerant after circling the periphery of the motor stator is thencaused to flow downwardly through the rotor and betweenithe rotor andstator to further effect a cooling of the same; and the provision of aconstruction as above described in which means are provided forseparating out oil from the refrigerant before it is passed upwardlyover the motor, and delivering such separated oil directly to the lowerpart of the housing.

Other objects of the invention include the pro,- vision of 'a novel formof lubricating means for the various parts of a motor-compressor unit;the provision of. a sealed, motor-compressor unit having means forlubricating the parts thereof so constructed and arranged as to keep thelubricant substantially out of contact-with the rotor and stator of thedriving motor; the provision of means for lubricating a sealedmotor-compressor unit in which definite quantities of lubricant may befed to different moving parts of the unit; the provision of alubrication system for a sealed motor-compressor unit which eliminatesthe necessity of requiring any separate lubricant circulating mechanism;and the provision of a construction as above described in which aportion of an entrapped mass of lubricant is fed to the interior of oneof the rotating parts of the mechanism and acted upon by centrifugalforce therein to distribute the lubricant in measured quantities todesired points of discharge.

Further objects of the invention include the provision of a sealedmotor-compressor unit having certain novel features of constructionfacili- 8 Claims. (Cl. 230-206) and emciently serviced and is relativelyeconomical to manufacture.

The above being among the objects of the present invention the sameconsists in certain novel features of construction and combinations ofparts to be hereinafter described with reference to the accompanyingdrawings, and then claimed, having the above and other objects in .view.

In the accompanying drawings which show a; suitable embodiment of thepresent invention and in which like numerals refer to like partsthroughout the several different views,

Fig. 1 is a vertical sectional view taken axially through amotor-compressor unit of my improved design;

Fig. 2 is a fragmentary transverse sectional view taken on the line 2-2of Fig. 1;

Fig. 3 is a fragmentary transverse sectional view taken on the line 3-3of Fig. 1;

. Fig. 4 is a plan view of the supporting member for the thrust washerfor the motor shaft in its original blank form and before being bent toshape;

Fig. 5 is an enlarged vertical sectional view taken transversely throughone of the cylinders as on the line 5--5 of Fig, 1; and,

Fig. 6 is an enlarged fragmentary horizontal sectional view taken on theline 88 of Fig. 1.

Referring to the accompanying drawings and particularly to Fig. 1 itwill be noted that the motor compressor unit includes a cast main bodyportion or housing I having an open top end which is closed by a cover 2through theuse of suitable bolts or screws as shown. The housing I hasan integral bottom wall centrally provided with an upstanding hollowboss to the bore of which extends through the bottom wall and isnormally closed by means of the plate 22 in conjunction with suitablebolts or screws as shown. While thedrawings show a unit having avertical axis, it is to be understood that most of the featating themanufacture and assembly of the entire structure whereby a moreefficient, more reliable device is provided that may be readily tures ofthis invention apply equally to an assembly having its shaft disposed atany other angle, in some cases employing means other than gravity formoving oil to the point from which centrifugal force moves it.

The upper end of the housing I is slightly larger than the lower end andis provided with a cylindrical bore in over the area where the stator 3for the electric driving motor is adapted to be received. As willhereinafter be more fully explaineda refrigerant circulating passage isformed' between the periphery of the stator 3 and I the housing I andfor this reason the periphery of the stator 3 is preferably arranged toform a substantially fluid tight seal with the walls of the bore Ia.This may be accomplished in several a light press fit in the bore Iawhere the periphery of the stator is of a continuous and unbrokennature; it may be accomplished by pressing a sheet metal or other sleeveinto the bore Ia and then pressing the stator 3 into such sleeve; or itmay be accomplished by surrounding the exterior of the stator with alight sheet metal or other sleeve of the required size to have a lightpress fit into the bore Ia. Where such sleeve is employed it is to beconsidered as a part of the stator 3 for the purpose of the presentinvention. The last described form is shown by way of illustration andthe surrounding sleeve is indicated at 3a. Its location axially of thehousing I isdetermined by means of a small step or shoulder Ib formed inthe bore Ia and against-which the lower end of the sleeve 3a is adaptedtoabut.

The rotor 4 for the driving motor is, of course,

- positioned within the stator 3 and concentric to it and is pressedupon the upper end of the drive shaft 5 which extends downwardlytherefrom to a point within andadjacent thelower end of the hollow bossIc on the bottom wall of the housing 1. Immediately below the rotor 4the shaft 5 is mounted in a removable. bearing 6 supported through itsintegral and oppositely extending lugs I upon the irmer end of a .pairof opposed and inwardly extending brackets or arms 8 formed integrallywith the housing I at their outer'ends. The peripheral surfaces of thelugs I are machined concentrically with the axis of-the bearing 6. andthe arcuate inner surfaces of shoulders on the arms or brackets 8 aremachined to form a flat surface and an arcuate shoulder 84: or locatingsurface to insure the concentricity of the bearing 6 with respect to theaxis of the housing I at all times. The lugs I are secured to thebrackets 8 by means of screws 68 passing down through the lugs andthreading into the brackets. The rotor 4 is provided with a plurality ofvertical holes 61 extending downwardly therethrough, each disposed withits axi at the same distance from the axis of the shaft 5 as the axis ofthe screws 68 so that any one of the holes 61 may be brought intoalignment with any one of the screws 68 and a screw driver projecteddown through any one of such aligned holes 61 to en- 'able the screws 68to be manipulated. As indicated in Fig. 2, the lefthand screw 68 islocated on a line passing through the axis of the shaft 5 disposed at anangle A with respect to the vertical center line of such figure, whilethe righthand screw 68 is located on a similar line disposed at an angleB to the right of such vertical center line. Corresponding screws 68which pass through the remaining lug I are similarly disposed, that is,the lefthand screw is disposed on a line extending at an angle A to theleft of the vertical center line and the remaining screw 68 on a linedisposed at an angle B to the right of the vertical center line. Theangles A and B being different, it will be appreciated that there is 4In on the bottom wall of the casing with its shoulder or flange abuttingthe upper end of the boss and overlying the same.

The shaft 5-is provided with an eccentric 3 and a counterweight I0,preferably formed integrally therewith, as indicated. The counterweightIII is shaped to permit it to be passed downwardly with the shaft 5between the right- -hand margins of the brackets 8, as viewed: in Fig.

2, and its radially outer surface is disposed at a smaller distance fromthe axis of the shaft 5 than,

the bore of the stator 3, so as to permit it to be passed through thestator 3. The angle between the lefthand margin of the brackets 8, asviewed in Fig. 2, is such and the inner ends of the brackets 8 are soshaped as to permit the eccentric 8 to be passed vertically through themwith the shaft 5 positioned concentrically of the housing I.

The weight of the shaft 5 and its rigidly connected parts, including therotor 4, eccentric 9 and counterweight I0, is carried on a thrust discor bearing I5, which is firmly clamped against the annular shoulderformed in the bottom portion of the bore of the hollow boss Ic by meansof a deformable sheet metal part 23 and is prevented only one positionin which the bearing 6 may be assembled to the brackets 8 and thisfeature is of importance in view of the fact that the bearin 6 ispreferably bored while secured in position in the casing I and may,therefore, be always rev turned to its original position after removal.

from turning by a .pin I511. The part 23 as originally blanked out isindicated in Fig. 4 and the various fingers thereof are then upwardlyand inwardly bent as indicated in Fig. 1. Originally the verticaldimension of the part 23 is greater than that capable of permitting itto be received between the thrust disc I5 and the cover 22 so that whenthe cover 22 is screwed into place the fingers of the part 23 aresumciently crushed down to .permit its reception in the space provided.The material from which the part 23 is constructed is preferably ofsufficient resiliency or deformability as to allow it to bend and tomaintain the thrust disc I5 firmly pressed up against its coaxialshoulder in the bore of the boss Ic after repeated disassembly andre-assembly.

A pair of cylinders 52 and 53, here shown as diametrically opposed, arecarried by the housing I at opposite sides thereof, the cylinders 52 and53 are shown aligned with each other and with their common axis passingthrough the eccentric 9 midway the height thereof. The cylinder 52 inthe construction shown is formed separately from the housing I and has areduced inner end closely received in a corresponding opening formed forits reception in the wall of the housing I. Two or more cylinders may beused and all removably attached like 52 if desired. The cylinder 53 inthe particular construction shown is formed integrally with the housingI. Each cylinder 52 and 53 is provided with a conventional valve plate48 and cylinder head '46. In the case of the cylinder 53, itscorresponding valve plate 48 and cylinder head 49 is secured to it bymeans of bolts 50 passing through the cylinder head and valve andthreaded into the cylinder. In the case of the cylinder 52, bolts 5|passing through the corresponding cylinder head 48 and valve plate 48also pass through the cylinder 52 and are threaded into the housing Inot only to secure the cylinder head and valve plate to the cylinder.but also to secure the cylinder to the housing I.

Each of the cylinders 52 and 53 is provided with a piston I4reciprocally received therein and each piston is connected by means of awrist pin 46 and connecting rod to the eccentric 8. The connecting rodI2 which connects the lefthand piston I4 with the eccentric 9. as viewedin Fig. 1,

- big end of the connecting rod I2 bears upon and is supported by theupper flanged face of the bearing II, while the equivalent face of therod I3 bears upon and is supported by the upper face of the lower forkedarm of the rod I2.

of the housing I at one end of the passageway '43. The housing Iadjacent the port I is pro-' of the housing I is cut away to provide avertical There may be two or more forked. rods with or without the onestraight rod, but preferably each forked rod has a bearing thatstraddles the cen ter line of its piston on the eccentric 9. one rodhaving a thrust bearing on bushing II andleach other one on another rod.

Although the particular type of piston and valve mechanism employed inconnection with the cylinders 52 and 53 forms no part of the presentinvention and may be of.any conventional type as, for instance, the typewherein the heads of the pistons are solid and a passage independentlyof the pistons communicates the compression space of each cylinder withthe interior of the housing I, for the purpose of illustration eachpiston I4 is shown as of the type having a gas passage I4a through thehead thereof and, as best illustrated in Fig. 5, the head of each pistonis fitted with a thin valve member 41 overlying the outer end thereofincluding a readily flexible portion 41a covering the corresponding gaspassage I40. and cooperating with the gas passage I4a to provide asuction port. The valve members 41 are fixed to the head of thecorresponding pistons I4 by means of screws 54 which, as illustrated inFig. 1, project beyond the end of the corresponding piston. It will beunderstood that the valve plates 48 are preferabLv recessed forreception of the heads of these screws 54 so as to provide for minimumclearance between the heads of the pistons and their corresponding valveplates at the outer ends of the piston stroke in accordance with theconventional practice. The discharge valve plate 48 may be similarly orotherwise fitted with suitable or conventional valves, and gas is pumpedby the pistons through these valves into the cylinder heads 49 fromwhich it may be conveyed by pipes or tubes 55, as illustrated in, Fig.2, through a suitable condenser and to an evaporator ,(not shown) of arefrigerating system in accordance with conventional practice.

After the refrigerant has been introduced into and expanded in theevaporator, it is conducted back into the housing I and delivered to thesuction side of the piston I4 for recompression. In returning thisexpanded refrigerant vapor to the interior of the housing I, it iscaused to flow into the housing I in such a manner as to absorb heatfrom both the stator 3 and rotor 4 of the driving motor thus to preventpossible overheating of the same. In order to eflect this result, thebore Ia which receives the stator 3 of the motor is centrally cut awayto form a relatively wide and shallow groove or passageway 63 almostcompletely annular in form but interrupted in its circular continuity bymeans of a vertical wall or abutment 86, as best illustrated in Fig. 2,thus imparting to the passageway 63 the form of a split ring or circle.The housing I is provided with an inlet or suction port ill extendingtherethrough which communicates with a short vertical recess OI on theinner surface passage 64 providing open communication between such endof the passage 63 and the upper I end of the housing I at a point abovethe stator 3. This is best shown in Figs. 1 and 3. Thus, re frigerantentering the port 60 is delivered to the recess II and then flows in aclockwise direction as viewed in Fig. 2 through the passage 63 betweenthe stator 3 and the housing I until it reaches the abutment 68 and thenflows upwardly through the passage 64 to the interior of the housing Iabove the stator 3 and rotor 4. This refrigerant then flows over theupper end of the stator and then downwardly through the space betweenthe stator 3 and rotor 4 as well as through the openings 61 in the rotor4 and into theiower portion of the housing I, where it is again inposition to be drawn through the pistons I 4 and recompressed.

It will be appreciated that in drawing the relatively cold refrigerantin gaseous form from the evaporator and causing it to flow substantiallycompletely around the outside of the stator 3 in relatively thinsheet-like form, and then causing it to flow up over the stator and thendown between the stator and rotor and through the rotor,

it will absorb a considerable amount of heat from the stator and rotorand eillciently serves as a means for preventing possible overheating ofthe motor.

Means is preferably provided for draining from passage 83 any liquid oilwhich is being carried through the system with the refrigerant anddelivering it to the lower portion of the housing I withoutnecessitating its being carried upwardly over the stator 3. This isdesirable not only to prevent such lubricant from building up into arelatively solid body in the passage 83 and thereby interfering withtheproper flow of refrigerant through the passage 63, but also to keepit out of contact with the windings of the motor. Separation of oilparticles from the refrigerant and collection thereof on the housingwall in passage 63 is effected by centrifugal force. The draining isaccomplished by providing a groove 65, shown in Figs. 1 and 2, in theinterior wall of the housin I and connecting the discharge end of thepassage 83 with the interior of the housing below the stator 3. In otherwords, the groove or passage 85 short circuits the discharge end of thepassage 63 to the lower portion of the interior of the housing I. Anyliquid particles of oil in the refrigerant introduced into thepassageway 83 tend to become separated out of the refrigerant vapor bycoming into contact with and tend tooling to the interior walls of thepassage 63, and gradually work around to the discharge side thereof and,upon reaching the area of the groove 35, will simply flow bygravity'down the groove 65 and into the lower portion of the housing I.The

size of the passageway 35 while suillciently large to take care of anyusual volume of lubricant that might find its way into the passageway 33still is sui'flciently small as to permit only a limited volume ofgaseous refrigerant to flowthereresponding with the level of the presentinvention and is accomplished as follows.

The bottom of the housing I, and particularly that portion thereof belowthe lower edges of the cylinders 52 and 53, constitutes a lubricantreservoir and holds a body of oil I8 therein. The drive shaft isprovided with a bore I6 of relatively large diameter therein whichextends from the lower end of the shaft 5 to a point preferably withinthe upper bearing 3. The upper end of the bore I 3 is vented to theinterior of the housing I by means of a vertical vent passage I1extending upwardly to a point between the upper end of the bearing 3 andthe lower end or the rotor 5 and which communicates with a transversevent passage I1 which leads to the exterior of the shaft 5 at thatpoint. The vent passages I1 and I1 are particularly brought out in Fig,2. The

bore of the boss Ic in which the bearing II is received is provided witha vertical groove 33 therein which extends from the shoulder againstwhich the disc I5 abuts to the upper end of the boss. The groove 33 iscommunicated with the 011 body I8 by means of a passage 32 through theboss. Adjacent its upper end the bearing II is provided with a hole orpassage 34 therein in 8 thus has the effect of forming the lower end ofthe bore I3 of the drive shaft 5 into a standpipe from which no oilbelow the top of the tube may flow downwardly through the tube 25 andback into the reservoir -I8.

The bore of tube 25 may be of such diameter as to regulate the rate ofoil flow into bore I6 of shaft 5, particularly in case the shaft ishorizontally disposed. The centrifugal pumping of oil is effective in ashaft disposed at any angle.

When the unit is operating and the shaft 5 therefor rotating, this oilwithin the bore I6 is acted upon by, centrifugal force and caused toassume the shape indicated at 21 in Fig. 1. That is, it is caused toclimb the sides of the bore It in shell-like form of graduallydecreasing thickness. It is this body of oil 21 that is employed tolubricate the wearing surfaces of the unit above the bearing II, andprovides a means bywhich a metered amount of lubricant may be fed tothese other wearing surfaces. This metering of the body of oil 21 to thevarious wearing surfaces is accomplished by the use of metering or porttubes such as 28. These metering or port tubes 28 may be employed at anyposition in the bore I3 where it is desired to lead off lubricant to awearing or other surface, except that none is required at the alignmentwith the groove or passage 33 and the exterior surface of the driveshaft 5, is provided a with a spiral groove in its surface, the upperportion of, which sweeps over the passage 34. The

passage 34 is below the normal level of the oil body I3 so that oil fromthe body in seeking its level flows under gravity through the passage32, channel 33 and through the passage 34 to the surface of the driveshaft 5 within the bushing II and rotation of the shaft 5 causes the oilto be fed to the spiral groove 35 and carried downwardly between theshaft 5 and the bore of the bushing II, thus providing a lubrication forthe drive shaft 5 in the lower bearing I I and also aiding in preventingthe escape of oil from the bore I6 of the shaft 5 past the lower end ofthe shaft and the thrust disc I5, as will hereinafter be more apparent.The hand or pitch of the spiral or helical groove 35 will depend uponthe direction of rotation of the shaft 5, the shaft 5 in the case shownbeing considered as turning in a clockwise direction as viewed lookingdown on top of the unit, and in such case the grooves 35 will belefthanded or will have a lefthand pitch.

The lower portion of the boss It: in which the bearing II is received,is provided with a passage 20 therethrough connecting the lower portionof the 011 body I8 with the chamber 2I formed between the lower face ofthe thrust disc I5 and the closure plate 22 so as to provide for thefree flow of oil to the chamber 2|. -The thrust disc I5 centrallycarries an upstanding tube 25 which projects upwardly into the bore itof the drive shaft to a point materially above the lower end of theshaft 5 but preferably upwardly to a point somewhat below the minimumlevel of the lubricant body I3. The tube 25 is suitably fixed and sealedto the disc I5. Thus, the oil in the reservoir or oil body I8 may flowfreely through the passage '20 into the chamber H and then up throughthe tube 25 into the hollow interior of the lower end of the drive shaft'5 where, when the shaft 5 is not rotating, it will find a level coroilbody I8 at a point above the top of the tube extreme top of the oil body21, but in the present case only one such metering or port tube 28 isshown by way of illustration. This is shown at a position where it willlead off lubricant from the oil body 21 to the wearing surfaces betweenthe eccentric 9 and the connecting rods I2 and I3 at an area adjacentthe upper side of the connecting rod I3 and the uppersfork of theconnecting rod I2. The eccentric 9 for this purpose is provided with, aradial passage-29 communicating the bore I3 with the exterior surface ofthe cocentric 3 at the point indicated and described. The port tube 28is fitted into the inner end of the passage 23. As best indicated inFigs. 1 and 6, the metering or port tube 28 is in the form of anapertured plug pressed into the inner end of the passage '29 and itsinner end is enlarged to provide a shoulder 28a which engages the wallsof the bore I3 and limits radially outward movement of the tube 28 inthe passage 29.

The amount of oil from the body 21 which may flow through the tube 28 isdependent upon two things, namely, the size of the bore in the tube 28and also the depth which the radially inner end of the tube 28 issubmerged radially inthe body of oil 21. This last feature is controlledby the axial thickness of the shoulder 28a and usually will be such thatit will lie slightly under the inner surface of the oil body 21 and theoil which passes through it will thus be more or less skimmed from theinner surface of the oil body 21 during operation of the unit. The oilwhich is skimmed off of the oil body 21 by the metering or port tube 28will pass through the passage 29 to the wearing surfaces between theconnecting rods and the eccentric and will also bethrown off radiallyinto. the bore of the cylinders 52 and 53 whereit will lubricate thewearing surfaces of the pistons and cylinders and also the wearingsurfaces between the pins 46 and the pistons I4 and the outer end of therods I2 and I3 and the piston bosses. The oil that is fed out throughthe port tube 28 or other lubricant discharge opening from the oil body21 is continuously replaced in the bore I6 by oil flowing into the boreI'B by gravity from the oil body I8. The port tube 23 may be 25. Thetube 25 :5 readily inserted in place in the passage 29 from the bore I8by means of a suitable tool prepared for that purpose.

The size-of the bore I6 is preferably so proportioned with respect tothe speed of rotation of the shaft and its vertical. angularorhorizontal arrangement that the oil body;2| will be elevated or moved toa point within the bearing 6, and within the portion of such bearingnearer its oil inlet the shaft '6 is provided with a radial passage 80therethrough communicating the bore I6 with the exterior surface of theshaft within the nearer end of the bearing 6. The exterior surface oftheshal't 5 within the length of t hear. ing 6 is preferably providedwith a righthand (when the shaft turns in the direction previouslyassumed) spiral groove cut therein into which the passage 30 dischargesand, accordingly, lubricant from the farther end of the body 21 willpass out through the passage 30 and into the groove 3| which will thuscarry the lubricant over the wearing surface between the shaft 5 andbearing 6 to insure ample lubrication of the same.

Preferably some means is provided for constantly filtering the lubricantas it flows from the reservoir I8 through the passages 32 and 2II.-

For this purpose a conical screen I9 may be provided between the boss Ic and the lower wall of the housing. The screen I9 may be fixed inposition and in sealed relation at both upper and lower ends thereofwith respect to the boss Ic and to the lower wall of the housing I bymeans of a split spring ring 36 snapped into a complementary grooveformed in the exterior surface of the boss Ic. Ifdesired, furtherfiltering elements may be employed and one of these may take the form ofan annular screen 24 of outwardly facing C-like section pressed betweenthe outer lower mar ins of the thrust disc I5 and thecover plate 22. Theheight of the screen 24 in free state is greater than the space providedfor it in the final assembly so that its opposite edges are crushed orsprung into dirt tight re-' lation with respect to the disc l5 and coverplate 22 when the plate 22 is tightened into position. An additionalfilter element may take theform of a screen 26 surrounding the upper endof the tube within the bore I6.

In order to provide electrical connection between power leads exteriorlyof the unit and the windings of the motor, a hole is drilled through thehousing I adjacent the upper'end thereof as illustrated in Figs. 1 and 2for each of the leads. An electrical conductor II projects through eachof the holes. Each conductor II is imbedded and sealed in a sleeve I2 ofsuitable electrical insulating material which in turn is received andsealed centrally within a threaded plug 13. Each plug I3 is threaded ingas-tight relation into the outerend of the corresponding opening. Theconstruction thus providing a gas-tight electrically insulatedconnection between the exterior and interior of the housing I. The outerends of the connectors II maybe threaded or otherwise formed forconnection to the usual electrical leads. Over the area where the innerends of the conductors II project into the interior of the housing I, anangle sectioned electrical insulating strip I8 is preferably providedthrough which the inner ends of the conductors proiect to the spacebetween the windings of the responding leads I5 of the motor may besoldered or otherwise secured. t

It will, of course, be appreciated that suitable gaskets are providedbetween all matching surfaces through which leakage might otherwiseoccur between the interior of the. housing I and the atmosphere. Thegasket 83 betweencylinder Handhousing I is made in various thicknesses.of which the proper one is selected to provide the desired clearancespace between the piston and' the cylinder head. A suitable set ofgaskets is provided to permit this adjustment to be made.

- Additionally provided are a gasket such as 8I between the cover 2 andthe housing I, gaskets 82 between the valve plates 48 and thecorresponding cylinders and cylinder heads, gasket 88 between thecylinder 52 and the housing I and the gasket 84 between the plate 22 andthe bottom wall of the housing I. The construction thus affords ahermetically sealed motor compressor unit in which an efllcient means isprovided for absorbing heat from the driving motor to prevent possibleoverheating of the same in service, means for separating out liquidparticles of lubricant from that portion of the stream of gaseousrefrigerant employed for cooling the motor and delivering out theseparated particles of liquid lubricant and short circuiting the passagethereof around the motor to the lower portion of the unit. It alsoprovides a means by which an ample and fully controlled amount oflubricant maybe fed to the various working parts of the unit withoutrequiringthe addition of any moving parts to the essential operatingparts 01' the mechanism.

In assembling the motor compressor unit above described, it will beappreciated that the stator 3 may be pressed into place either before orafter the rotor and its associated parts have been inserted. Before therotor I is pressed upon the shaft 5 the bearing 6 is positioned onstator 4 and the bore of the housing I. The in-',

ner ends. of the conductors II inwardly of the insulating strip 16 arepreferably notched to receive connector spring clips 14 to which thecorthe shaft and the screws 68 inserted through the lugs I. The pistonsI4 and their respective connecting rods I2 and I3 are inserted intoplace and then the rotor l and shaft 5 are fed downwardly into thehousing, the lower end of the shaft 5 is introduced into the bearing IIand the eccentric 9 is guided into the large-end of the connecting rodsI2 and I3. The inner ends of the brackets 8are sufficiently spaced fromone another to permit the passage of the eccentric 9 therethrough whenturned toward the left-hand cylinder 53, and the space between theopposite sides of the brackets 8 is sufliciently wide to permit thepassage of'the counterweight I0 therebetween as previously mentioned. Asthe parts are set into position the lugs I of the upper bearing 6 arebrought into pcsitionvabove the inner ends of the brackets 8, the screws68 are aligned with their corresponding openings in the ends of thebrackets 8 and a screw driver is then introduced down through one ormore of the holes 61 and the screws 63 are threaded into place. In thisrespect it will be recalled that because of the particular spacing ofthe screws 68 previously described there is only one rotatable positionof the bearing 6 with respect to .the housing I in which the screws 68may all the construction the stator 3 will be allowed to remain inposition unless it is desired to remove it for repair or replacement.

Formal changes may embodiment of the invention described .withoutdeparting from the spirit or. substance of the broad invention, thescope of which is commensurate with the appended claims.

he made in the specific below the level to which said sump is filledwith oil audits opposite end above said oil level, said shaft having alengthwise hole therein extending from its lower end to a distance abovesaid oil same, and compressor mechanism driven from said shaft.

4. In a motor-compressorunit of a refrigerating system, a gas-tight.housing enclosing the working parts of said unit, a vertical shaftforming a driving connection between said parts, said shaft, having anaxially located longitudinal hole therein, a closure for the lower endof said hole. and a fixed tube leading into said hole through saidclosure axially of said shaft, said shaft, hole. closure and tube beingso constructed and arranged as to lift oil within the shaft bore byvirtue of centrifugal force.

5. A motor-compressor unit comprising, in combination, a housing, amotor and a compressor driven therefrom sealed in said housing, a commonvertically directed shaft for said motor and level, a wall extendingacross and closing said hole at a position below said oil level, saidwall having an oil inlet port therein adjacent the axis of said shaft incommunication with said sump, a conduit extending upwardly within saidhole from said port to 'a point below said oil level, a bearing of saidunit located at least partly above said oil level, an oil outlet e fromsaid hole to said bearing, a motor in the upper portion, of said housingconnected to said shaft for driving the same, and compression mechanismin the lower portion of said housing receiving driving movement fromsaid shaft.

2. Amotor-compressor unit comprising, in combination, a sealed housing,an oil sump in a lower portion of said housing, a vertical shaftrotatably mounted in said housing and having one end below the level towhich said sump is filled with oil andits opposite end above said oillevel; said shaft having a hole therein extending lengthwise thereoffrom its lower end to a distance above said oil level, a wall extendingacross and closing said hole at a position below said oil level, saidwall having an oil inlet port therein adjacent the axis of said shaftand communicating with said sump, a conduit extending upwardly withinsaid hole from said port to a point below said oil level. a plurality ofbearings of said unit located at least in part above said all level andat different heights with respect to said oil level; an oil outletpassage from said hole to a lower one of said bearings, -a second outletpassage from said hole to a higher one of said bearings, a motor in theupper portion of said housing connected to said shaft for driving thesame, and compressor mechanism driven from said shaft.

3. A motor-compressor unit comprising, in combination, a housing, an oilsump in a lower portion of said housingm. shaft rotatably mounted insaid housing and having one end below the level to which said sump isfilled with oil and its opposite end above said 011 level, said shafthaving a hole therein extending lengthwise thereof from its lower end toa distance above said oil level, a wall extending across said hole at aposition below said oil level, an oil inlet port in said wall adjacentthe axis of said shaft in communication with said sump, a plurality ofbearings of said compressor, an oil sump in a lower portion of saidhousing, said shaft rotatably mounted in said housing and having one endbelow the level to which said sump is filled with oil and its oppositeend above said oil level, said shaft having a lengthwise hole thereinextending from its lower end to a distance above said oil level and avent passage leading from the first mentioned hole to an exteriorsurface of said shaft for the purpose of relieving gas pressure producedin said hole by the separation of vapor from the oil, a wall extendingacross said hole at a position below said oil level, said wall having anoil inlet port therein adjacent the axis of said shaft in communicationwith said sump. a conduit extending upwardly within said hole from isaid port to a point below said oil level, a bearing of said unitlocated at least partly above said oil level, an oil outlet passage fromsaid hole to said bearing, a motor in the upper portion'of said housingconnected to said shaft for driving the same, and compression mechanismin the lower portion of said housing receiving driving movement fromsaid shaft.

6. A motor-compressor unit comprising, in combination, a sealed housing,an oil sump in a lower portion of said housing, a vertically directedshaft rotatably mounted in said housin and having one end below thelevel to which said sump is filled with oil and its opposite end abovesaid oil level, a bearing for said shaft, said shaft having a lengthwisehole therein ex- "tending from its lower end to a distance above saidoil level, ascreen surrounding said bearing, a disc providing a thrustbearing for the lower end of said shaft forming a wall closing said holeat-the lower end ofsaid shaft, said thrust disc having an oil inlet porttherein adjacent the axis of said shaft in communication with said sump,a conduit extending upwardly within said unit located at least in partabove said oil level and at different heights with respect to said 011level, an oil outlet passage from said hole to a lower one of saidbearings, a second outlet passage from said hole to a higher one of saidbearings, said second passage having its inlet end at a greater radiusfrom the axis of said shaft than the inlet of the first said passage, amotor in said housing connected to said shaft for driving the hole fromsaid port to a point below said oil level, a bearing of said unitlocated at least partly above said oil level, an oil outlet passage fromsaid hole to said last mentioned bearing, a motor in the upper portionof said housing connected to said shaft for driving the same, andcompression mechanism in the lower portion of said housing receivingdriving movement fromsaid shaft.

7. Refrigerating mechanism comprising, in combination, a compressor, amotor for, driving said compressor, a vertical shaftconnecting saidmotor and compressor, a gas-tight housing enclosing the moving parts ofsaid motor and compressor, a bearing at the bottom of said housing forthe lower end of said shaft, an oil reservoir in said housingsurrounding said bearing, a screen surrounding said bearing, said shafthaving a hole therein extending from the lower end thereof Numberupwardly therein, a disc closing the lower (and 2,138,093 of said shaftand providing a. thrust, bearing 2,113,691 therefor, said shaft having ahelical groove in 1,081,159 that portion thereof embraced by thefirstmeu- 3 1,738,104 tioned bearing whereby to feed oil downwardly1,696,436 against said thrust disc to assist in sealing the 1,727,049Joint between it and said shaft, and. an oil pas- 2,125,645 sage leadinginto said first mentioned bearing 2,062,052

from the annular space within said screen. 2,134,936 8. In a sealedmotor-compressor assembly, in 1,934,482 combination, a gas-tight housingenclosing the 2,200,222 working parts of said assembly, a motorincluding 2,045,014 a rotor located in said housing, a compressor2,033,437 having working parts driven by d motor and 2,035,276 sealedfrom atmosphere by said housing, a. ver- 2,199,486 tically directedshaft connecting said motor and 1,673,157 compressor for driving thelatter, a bore in said 1,892,332 shaft extending lengthwise of it for atleast part 2,065,162 of itslength, a stationary wail closing an open 591137 end of said bore, an oil conduit extending through 1,733,104, said.wall into said bore at approximately the 2 43315 axis of rotation ofsaid shaft. means fo s np 970,487 ing oil to said bore through said oilconduit, and 1,840,045 an oil outlet port leading from said bore for ad0 delivery 0! oil to a bearing surface of said as- 5 4 sembly. 2,228,364GLENN MUFFLY. 1 7 03 4 REFERENCES crrnn I I 113121332 The followingreferences are of record in the flleof this patent: Numb'er UNI'IEDSTATES PATENTS 734 91 Number I Name Date 2,146,097 Touborg Feb. 7, 1989'14 Name Date Feldbush et al, Nov. 29, 1938 Heller Apr, 12, 1938 ShipleyDec. 9, 1913 Hall Dec. 3, 1929 'Gray Dec. 25, 1928 Cobb Sept. 3, 1929Money Aug. 2, 1938 Horlacher Nov. 21, 1936 Getcheii et a1. Nov. 1, 1938Bixler Nov. '7, 1933 Tarleton y 7, 1940 Kenney et al. June 23, 1936McCune et ai.- r. 19, 1936 Replogle Mar. 29, 1936 Doeg May 7, 1910Powei1 June 12, 1928 Des Roches Dec. 27, 1932 Trask Dec, 22, 1936 MilesOct. 5, 1697 Hall Dec. 3, 1929 Smith et a1. June 2, 1936, Gardner Sept.20, 1910 McCormack Jan. 5, 1932 Johnson Feb. 16, 1937 McCune Jan. 25,1938 Philip Jan. 14, 1941 6mm Nov. 4, 1930 Blood et a1. Aug. 9, 1932Rataiczak Sept. 10, 1940 FOREIGN PATENTS Country Date mince Feb. 5. 1932

